[libvirt] [PATCH 05/13] Pass prefix rather than netmask into iptables functions

Laine Stump laine at laine.org
Mon Dec 20 08:03:17 UTC 2010


IPv6 will use prefix exclusively, and IPv4 will also optionally be
able to use it, and the iptables functions really need a prefix
anyway, so use the new virNetworkDefPrefix() function to send prefixes
into iptables functions instead of netmasks.

Also, in a couple places where a netmask is actually needed, use the
new private API function for it rather than getting it directly. This
will allow for cases where no netmask or prefix is specified (it
returns the default for the current class of network.)
---
 src/network/bridge_driver.c |   91 +++++++++++++++++++++++++++++++------------
 src/util/iptables.c         |   63 +++++++++++++++---------------
 src/util/iptables.h         |   16 ++++----
 3 files changed, 105 insertions(+), 65 deletions(-)

diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 1ae3924..b592840 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -586,11 +586,19 @@ cleanup:
 static int
 networkAddMasqueradingIptablesRules(struct network_driver *driver,
                                     virNetworkObjPtr network) {
+    int prefix = virNetworkDefPrefix(network->def);
+
+    if (prefix < 0) {
+        networkReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Invalid prefix or netmask for '%s'"),
+                           network->def->bridge);
+        goto masqerr1;
+    }
 
     /* allow forwarding packets from the bridge interface */
     if (iptablesAddForwardAllowOut(driver->iptables,
                                    &network->def->ipAddress,
-                                   &network->def->netmask,
+                                   prefix,
                                    network->def->bridge,
                                    network->def->forwardDev) < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -602,7 +610,7 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
     /* allow forwarding packets to the bridge interface if they are part of an existing connection */
     if (iptablesAddForwardAllowRelatedIn(driver->iptables,
                                          &network->def->ipAddress,
-                                         &network->def->netmask,
+                                         prefix,
                                          network->def->bridge,
                                          network->def->forwardDev) < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -637,7 +645,7 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
     /* First the generic masquerade rule for other protocols */
     if (iptablesAddForwardMasquerade(driver->iptables,
                                      &network->def->ipAddress,
-                                     &network->def->netmask,
+                                     prefix,
                                      network->def->forwardDev,
                                      NULL) < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -649,7 +657,7 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
     /* UDP with a source port restriction */
     if (iptablesAddForwardMasquerade(driver->iptables,
                                      &network->def->ipAddress,
-                                     &network->def->netmask,
+                                     prefix,
                                      network->def->forwardDev,
                                      "udp") < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -661,7 +669,7 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
     /* TCP with a source port restriction */
     if (iptablesAddForwardMasquerade(driver->iptables,
                                      &network->def->ipAddress,
-                                     &network->def->netmask,
+                                     prefix,
                                      network->def->forwardDev,
                                      "tcp") < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -675,25 +683,25 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
  masqerr5:
     iptablesRemoveForwardMasquerade(driver->iptables,
                                     &network->def->ipAddress,
-                                    &network->def->netmask,
+                                    prefix,
                                     network->def->forwardDev,
                                     "udp");
  masqerr4:
     iptablesRemoveForwardMasquerade(driver->iptables,
                                     &network->def->ipAddress,
-                                    &network->def->netmask,
+                                    prefix,
                                     network->def->forwardDev,
                                     NULL);
  masqerr3:
     iptablesRemoveForwardAllowRelatedIn(driver->iptables,
                                         &network->def->ipAddress,
-                                        &network->def->netmask,
+                                        prefix,
                                         network->def->bridge,
                                         network->def->forwardDev);
  masqerr2:
     iptablesRemoveForwardAllowOut(driver->iptables,
                                   &network->def->ipAddress,
-                                  &network->def->netmask,
+                                  prefix,
                                   network->def->bridge,
                                   network->def->forwardDev);
  masqerr1:
@@ -703,11 +711,19 @@ networkAddMasqueradingIptablesRules(struct network_driver *driver,
 static int
 networkAddRoutingIptablesRules(struct network_driver *driver,
                                virNetworkObjPtr network) {
+    int prefix = virNetworkDefPrefix(network->def);
+
+    if (prefix < 0) {
+        networkReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Invalid prefix or netmask for '%s'"),
+                           network->def->bridge);
+        goto routeerr1;
+    }
 
     /* allow routing packets from the bridge interface */
     if (iptablesAddForwardAllowOut(driver->iptables,
                                    &network->def->ipAddress,
-                                   &network->def->netmask,
+                                   prefix,
                                    network->def->bridge,
                                    network->def->forwardDev) < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -719,7 +735,7 @@ networkAddRoutingIptablesRules(struct network_driver *driver,
     /* allow routing packets to the bridge interface */
     if (iptablesAddForwardAllowIn(driver->iptables,
                                   &network->def->ipAddress,
-                                  &network->def->netmask,
+                                  prefix,
                                   network->def->bridge,
                                   network->def->forwardDev) < 0) {
         networkReportError(VIR_ERR_SYSTEM_ERROR,
@@ -734,7 +750,7 @@ networkAddRoutingIptablesRules(struct network_driver *driver,
  routeerr2:
     iptablesRemoveForwardAllowOut(driver->iptables,
                                   &network->def->ipAddress,
-                                  &network->def->netmask,
+                                  prefix,
                                   network->def->bridge,
                                   network->def->forwardDev);
  routeerr1:
@@ -870,40 +886,50 @@ networkRemoveIptablesRules(struct network_driver *driver,
                                            network->def->bridge, 68);
     }
     if (network->def->forwardType != VIR_NETWORK_FORWARD_NONE) {
+        int prefix = virNetworkDefPrefix(network->def);
+
+        if (prefix < 0) {
+            networkReportError(VIR_ERR_INTERNAL_ERROR,
+                               _("Invalid prefix or netmask for '%s'"),
+                               network->def->bridge);
+            goto error;
+        }
+
         if (network->def->forwardType == VIR_NETWORK_FORWARD_NAT) {
             iptablesRemoveForwardMasquerade(driver->iptables,
                                             &network->def->ipAddress,
-                                            &network->def->netmask,
+                                            prefix,
                                             network->def->forwardDev,
                                             "tcp");
             iptablesRemoveForwardMasquerade(driver->iptables,
                                             &network->def->ipAddress,
-                                            &network->def->netmask,
+                                            prefix,
                                             network->def->forwardDev,
                                             "udp");
             iptablesRemoveForwardMasquerade(driver->iptables,
                                             &network->def->ipAddress,
-                                            &network->def->netmask,
+                                            prefix,
                                             network->def->forwardDev,
                                             NULL);
             iptablesRemoveForwardAllowRelatedIn(driver->iptables,
                                                 &network->def->ipAddress,
-                                                &network->def->netmask,
+                                                prefix,
                                                 network->def->bridge,
                                                 network->def->forwardDev);
         } else if (network->def->forwardType == VIR_NETWORK_FORWARD_ROUTE)
             iptablesRemoveForwardAllowIn(driver->iptables,
                                          &network->def->ipAddress,
-                                         &network->def->netmask,
+                                         prefix,
                                          network->def->bridge,
                                          network->def->forwardDev);
 
         iptablesRemoveForwardAllowOut(driver->iptables,
                                       &network->def->ipAddress,
-                                      &network->def->netmask,
+                                      prefix,
                                       network->def->bridge,
                                       network->def->forwardDev);
     }
+error:
     iptablesRemoveForwardAllowCross(driver->iptables, network->def->bridge);
     iptablesRemoveForwardRejectIn(driver->iptables, network->def->bridge);
     iptablesRemoveForwardRejectOut(driver->iptables, network->def->bridge);
@@ -1007,17 +1033,23 @@ static int networkCheckRouteCollision(virNetworkObjPtr network)
 {
     int ret = -1, len;
     unsigned int net_dest;
+    virSocketAddr netmask;
     char *cur, *buf = NULL;
     enum {MAX_ROUTE_SIZE = 1024*64};
 
-    if (!VIR_SOCKET_IS_FAMILY(&network->def->ipAddress, AF_INET) ||
-        !VIR_SOCKET_IS_FAMILY(&network->def->netmask, AF_INET)) {
+    if (!VIR_SOCKET_IS_FAMILY(&network->def->ipAddress, AF_INET)) {
         /* Only support collision check for IPv4 */
         return 0;
     }
 
+    if (virNetworkDefNetmask(network->def, &netmask) < 0) {
+        networkReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Failed to get netmask of '%s'"),
+                           network->def->bridge);
+    }
+
     net_dest = (network->def->ipAddress.data.inet4.sin_addr.s_addr &
-                network->def->netmask.data.inet4.sin_addr.s_addr);
+                netmask.data.inet4.sin_addr.s_addr);
 
     /* Read whole routing table into memory */
     if ((len = virFileReadAll(PROC_NET_ROUTE, MAX_ROUTE_SIZE, &buf)) < 0)
@@ -1070,7 +1102,7 @@ static int networkCheckRouteCollision(virNetworkObjPtr network)
         addr_val &= mask_val;
 
         if ((net_dest == addr_val) &&
-            (network->def->netmask.data.inet4.sin_addr.s_addr == mask_val)) {
+            (netmask.data.inet4.sin_addr.s_addr == mask_val)) {
             networkReportError(VIR_ERR_INTERNAL_ERROR,
                                _("Network is already in use by interface %s"),
                                iface);
@@ -1126,9 +1158,18 @@ static int networkStartNetworkDaemon(struct network_driver *driver,
         goto err_delbr;
     }
 
-    if (VIR_SOCKET_HAS_ADDR(&network->def->netmask) &&
-        (err = brSetInetNetmask(driver->brctl, network->def->bridge,
-                                &network->def->netmask))) {
+    virSocketAddr netmask;
+
+    if (virNetworkDefNetmask(network->def, &netmask) < 0) {
+
+        networkReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("bridge  '%s' has an invalid netmask or IP address"),
+                           network->def->bridge);
+        goto err_delbr;
+    }
+
+    if ((err = brSetInetNetmask(driver->brctl, network->def->bridge,
+                                &netmask))) {
         virReportSystemError(err,
                              _("cannot set netmask on bridge '%s'"),
                              network->def->bridge);
diff --git a/src/util/iptables.c b/src/util/iptables.c
index effd81b..89e05b7 100644
--- a/src/util/iptables.c
+++ b/src/util/iptables.c
@@ -276,25 +276,24 @@ iptablesRemoveUdpInput(iptablesContext *ctx,
 
 
 static char *iptablesFormatNetwork(virSocketAddr *netaddr,
-                                   virSocketAddr *netmask)
+                                   int prefix)
 {
     virSocketAddr network;
-    int prefix;
     char *netstr;
     char *ret;
 
-    if (!VIR_SOCKET_IS_FAMILY(netaddr, AF_INET) ||
-        !VIR_SOCKET_IS_FAMILY(netmask, AF_INET)) {
+    if (!VIR_SOCKET_IS_FAMILY(netaddr, AF_INET)) {
         iptablesError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                       _("Only IPv4 addresses can be used with iptables"));
         return NULL;
     }
 
     network = *netaddr;
-    network.data.inet4.sin_addr.s_addr &=
-        netmask->data.inet4.sin_addr.s_addr;
-
-    prefix = virSocketGetNumNetmaskBits(netmask);
+    if (virSocketAddrMaskByPrefix(&network, prefix) < 0) {
+        iptablesError(VIR_ERR_INTERNAL_ERROR, "%s",
+                      _("Failure to mask address"));
+        return NULL;
+    }
 
     netstr = virSocketFormatAddr(&network);
 
@@ -315,7 +314,7 @@ static char *iptablesFormatNetwork(virSocketAddr *netaddr,
 static int
 iptablesForwardAllowOut(iptablesContext *ctx,
                         virSocketAddr *netaddr,
-                        virSocketAddr *netmask,
+                        int prefix,
                         const char *iface,
                         const char *physdev,
                         int action)
@@ -323,7 +322,7 @@ iptablesForwardAllowOut(iptablesContext *ctx,
     int ret;
     char *networkstr;
 
-    if (!(networkstr = iptablesFormatNetwork(netaddr, netmask)))
+    if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
         return -1;
 
     if (physdev && physdev[0]) {
@@ -362,11 +361,11 @@ iptablesForwardAllowOut(iptablesContext *ctx,
 int
 iptablesAddForwardAllowOut(iptablesContext *ctx,
                            virSocketAddr *netaddr,
-                           virSocketAddr *netmask,
+                           int prefix,
                            const char *iface,
                            const char *physdev)
 {
-    return iptablesForwardAllowOut(ctx, netaddr, netmask, iface, physdev, ADD);
+    return iptablesForwardAllowOut(ctx, netaddr, prefix, iface, physdev, ADD);
 }
 
 /**
@@ -385,11 +384,11 @@ iptablesAddForwardAllowOut(iptablesContext *ctx,
 int
 iptablesRemoveForwardAllowOut(iptablesContext *ctx,
                               virSocketAddr *netaddr,
-                              virSocketAddr *netmask,
+                              int prefix,
                               const char *iface,
                               const char *physdev)
 {
-    return iptablesForwardAllowOut(ctx, netaddr, netmask, iface, physdev, REMOVE);
+    return iptablesForwardAllowOut(ctx, netaddr, prefix, iface, physdev, REMOVE);
 }
 
 
@@ -399,7 +398,7 @@ iptablesRemoveForwardAllowOut(iptablesContext *ctx,
 static int
 iptablesForwardAllowRelatedIn(iptablesContext *ctx,
                               virSocketAddr *netaddr,
-                              virSocketAddr *netmask,
+                              int prefix,
                               const char *iface,
                               const char *physdev,
                               int action)
@@ -407,7 +406,7 @@ iptablesForwardAllowRelatedIn(iptablesContext *ctx,
     int ret;
     char *networkstr;
 
-    if (!(networkstr = iptablesFormatNetwork(netaddr, netmask)))
+    if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
         return -1;
 
     if (physdev && physdev[0]) {
@@ -450,11 +449,11 @@ iptablesForwardAllowRelatedIn(iptablesContext *ctx,
 int
 iptablesAddForwardAllowRelatedIn(iptablesContext *ctx,
                                  virSocketAddr *netaddr,
-                                 virSocketAddr *netmask,
+                                 int prefix,
                                  const char *iface,
                                  const char *physdev)
 {
-    return iptablesForwardAllowRelatedIn(ctx, netaddr, netmask, iface, physdev, ADD);
+    return iptablesForwardAllowRelatedIn(ctx, netaddr, prefix, iface, physdev, ADD);
 }
 
 /**
@@ -473,11 +472,11 @@ iptablesAddForwardAllowRelatedIn(iptablesContext *ctx,
 int
 iptablesRemoveForwardAllowRelatedIn(iptablesContext *ctx,
                                     virSocketAddr *netaddr,
-                                    virSocketAddr *netmask,
+                                    int prefix,
                                     const char *iface,
                                     const char *physdev)
 {
-    return iptablesForwardAllowRelatedIn(ctx, netaddr, netmask, iface, physdev, REMOVE);
+    return iptablesForwardAllowRelatedIn(ctx, netaddr, prefix, iface, physdev, REMOVE);
 }
 
 /* Allow all traffic destined to the bridge, with a valid network address
@@ -485,7 +484,7 @@ iptablesRemoveForwardAllowRelatedIn(iptablesContext *ctx,
 static int
 iptablesForwardAllowIn(iptablesContext *ctx,
                        virSocketAddr *netaddr,
-                       virSocketAddr *netmask,
+                       int prefix,
                        const char *iface,
                        const char *physdev,
                        int action)
@@ -493,7 +492,7 @@ iptablesForwardAllowIn(iptablesContext *ctx,
     int ret;
     char *networkstr;
 
-    if (!(networkstr = iptablesFormatNetwork(netaddr, netmask)))
+    if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
         return -1;
 
     if (physdev && physdev[0]) {
@@ -532,11 +531,11 @@ iptablesForwardAllowIn(iptablesContext *ctx,
 int
 iptablesAddForwardAllowIn(iptablesContext *ctx,
                           virSocketAddr *netaddr,
-                          virSocketAddr *netmask,
+                          int prefix,
                           const char *iface,
                           const char *physdev)
 {
-    return iptablesForwardAllowIn(ctx, netaddr, netmask, iface, physdev, ADD);
+    return iptablesForwardAllowIn(ctx, netaddr, prefix, iface, physdev, ADD);
 }
 
 /**
@@ -555,11 +554,11 @@ iptablesAddForwardAllowIn(iptablesContext *ctx,
 int
 iptablesRemoveForwardAllowIn(iptablesContext *ctx,
                              virSocketAddr *netaddr,
-                             virSocketAddr *netmask,
+                             int prefix,
                              const char *iface,
                              const char *physdev)
 {
-    return iptablesForwardAllowIn(ctx, netaddr, netmask, iface, physdev, REMOVE);
+    return iptablesForwardAllowIn(ctx, netaddr, prefix, iface, physdev, REMOVE);
 }
 
 
@@ -722,7 +721,7 @@ iptablesRemoveForwardRejectIn(iptablesContext *ctx,
 static int
 iptablesForwardMasquerade(iptablesContext *ctx,
                           virSocketAddr *netaddr,
-                          virSocketAddr *netmask,
+                          int prefix,
                           const char *physdev,
                           const char *protocol,
                           int action)
@@ -730,7 +729,7 @@ iptablesForwardMasquerade(iptablesContext *ctx,
     int ret;
     char *networkstr;
 
-    if (!(networkstr = iptablesFormatNetwork(netaddr, netmask)))
+    if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
         return -1;
 
     if (protocol && protocol[0]) {
@@ -792,11 +791,11 @@ iptablesForwardMasquerade(iptablesContext *ctx,
 int
 iptablesAddForwardMasquerade(iptablesContext *ctx,
                              virSocketAddr *netaddr,
-                             virSocketAddr *netmask,
+                             int prefix,
                              const char *physdev,
                              const char *protocol)
 {
-    return iptablesForwardMasquerade(ctx, netaddr, netmask, physdev, protocol, ADD);
+    return iptablesForwardMasquerade(ctx, netaddr, prefix, physdev, protocol, ADD);
 }
 
 /**
@@ -815,11 +814,11 @@ iptablesAddForwardMasquerade(iptablesContext *ctx,
 int
 iptablesRemoveForwardMasquerade(iptablesContext *ctx,
                                 virSocketAddr *netaddr,
-                                virSocketAddr *netmask,
+                                int prefix,
                                 const char *physdev,
                                 const char *protocol)
 {
-    return iptablesForwardMasquerade(ctx, netaddr, netmask, physdev, protocol, REMOVE);
+    return iptablesForwardMasquerade(ctx, netaddr, prefix, physdev, protocol, REMOVE);
 }
 
 
diff --git a/src/util/iptables.h b/src/util/iptables.h
index ed843ec..6f59b92 100644
--- a/src/util/iptables.h
+++ b/src/util/iptables.h
@@ -45,34 +45,34 @@ int              iptablesRemoveUdpInput          (iptablesContext *ctx,
 
 int              iptablesAddForwardAllowOut      (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 int              iptablesRemoveForwardAllowOut   (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 
 int              iptablesAddForwardAllowRelatedIn(iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 int              iptablesRemoveForwardAllowRelatedIn(iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 
 int              iptablesAddForwardAllowIn       (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 int              iptablesRemoveForwardAllowIn    (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *iface,
                                                   const char *physdev);
 
@@ -93,12 +93,12 @@ int              iptablesRemoveForwardRejectIn   (iptablesContext *ctx,
 
 int              iptablesAddForwardMasquerade    (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *physdev,
                                                   const char *protocol);
 int              iptablesRemoveForwardMasquerade (iptablesContext *ctx,
                                                   virSocketAddr *netaddr,
-                                                  virSocketAddr *netmask,
+                                                  int prefix,
                                                   const char *physdev,
                                                   const char *protocol);
 int              iptablesAddOutputFixUdpChecksum (iptablesContext *ctx,
-- 
1.7.3.4




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